stephen colbert is called before congress. is this a joke or expert testimony? >> mark preston live at the cnnpolitics.com desk for us this morning. mark, there's a lot to talk about this morning. >> there sure is john, there sure is, kiran. stephen colbert has capitol hill abuzz. fridays here in washington tend to be kind of sleepy. but today stephen colbert of comedy central is going to be on capitol hill testifying about this very hot-button issue of immigration. you know, he spent a day on a corn farm up in new york. spending really walking a day in the shoes of a migrant farm worker. he's been talking about it on his show the last couple of nights. i will tell you having watched those clips, it'll be interesting to see what he does say during this hearing. i suspect he's going to be probably sympathetic to the migrant farm worker. so stephen colbert on capitol hill, a story we're following here at cnn. very interesting story. but check this out, as well. governor chris cristy takes on a heckler. the former ebay ceo running for governor, and a heckler got up